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File: STEM-Logo1.jpg (274 KB, 1297x736)
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What classes are you taking this semester anons? What are you looking forward to the most? The least?

Personally, Im taking:
-Plant Physiology
-Linear Algebra
-Environment and Society
-History 101
Im studying abroad this semester, so of course my courseload is a lot lighter than Im used to. I'm really excited for plant phys and linear algebra, because I'm trying to figure out if I want to go into plant synthetic biology or not. Im really dreading history though.

How about you?
273 replies and 18 images omitted. Click here to view.
>>
> Functional spaces and fourrier analysis
> Measure theory
> Differential Geometry
> Cryptanalysis and mathematical cryptology
> Statistical foundations of machine learning

I'm feeling comfy in my top EU-uni compared to these nigger tier american programs i'm seeing
>>
>>9455127
>learning java instead of C++
pajeet uni
>>
>>9455143
I forgot one. We see C and C++ as part of our systems programming course.
>>
>>9454849
Well, at least it's all interesting
>>9454858
I reckon my grades will be better for these courses than previous ones... less tedium, ya know?
>>9455019
Why?
>>
>>9441387
next semester will be
>Nuclear Physics
>Quantum Physics (Repeat from last semester)

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What do you call properties of objects that are not its shape?

For example, lets say for the sake of argument that the shape of a neutron is a sphere. How would you describe the set of properties it had that were not its shape. Would they be classified as "non-shape" properties?

Non-physical does not work since mass and charge are both physical but are not the shape of the object.

Maybe "Amorphous properties?" could you help you out here?
>>
>>9455290

kek at image
>>
Im not aware of the existence of a system of classication such as this. makes me think what you're looking for are intensive and extensive properties.

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Is he right or wrong?
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>>9451729
test
>>
>>9451738
The afterlife will be like the 80s? Cool.
>>
>>9454498
And the five year old child doesn’t want the birthday party to end. The obvious reality is that it does.
>>
>>9454855
>The second law of thermodynamics states that the total entropy can never decrease over time for an isolated system

Let's see if you're bait, retarded, or both.
1. What is the definition of an isolated system?
2. What is the thermodynamic nature of the system in which human beings evolved?
3. Knowing the answer to the previous two questions, does the second law of thermodynamics apply to said system?
>>
>>9451729
He died decades ago. I don't care what they program that doppelganger's computer to say

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Anybody have any good resources on nuclear models in general esp. w/r/t nuclear shell models. Like, I understand that L is no longer bounded and theres a sequence of seemingly arbitrary orbitals that create the magic numbers. How do I take the next step?
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>>
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I'm half asleep and don't know shit about this so ignore me if you please, but could electron shells exist as a sphere in 4 spacial dimensions, and we can only observe them as a torus because of the extra dimension?
>>
>>9454209
Not sure about that fourth dimension, but we don't actually observe electrons, we just predict their probability of existing in a position, and localized areas of highest probability become shells.

Here's an interesting paper if you're not too half-asleep for it
http://ieeexplore.ieee.org/document/960938/
>>
>>9453984
It looks like you're talking about electron orbitals here, I was asking about nuclear orbitals.
>>
>>9453969
I don't know exactly what the nuclear shell model is, but it sounds like you're trying to describe angular momentum states

If you haven't studied finite-dimensional representations of SU(2) then that's the next step.
>>
Therea a bit on it in krane's introductory nuclear physics

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Being gay isn't normal. Should homosexuality occurring in nature mean nothing in the face of this statement because animals are mindless and therefore shouldn't be taken as a reference, or does it disprove it because of the same reason i.e. that animals, who operate on instinct, engage in it and therefore the occurrence of it in humans is also completely natural? If it were natural and not an aberration then why do only a minority of people experience it? Any logical line of reasoning will lead to the conclusion that it's not supposed to happen. Is there any more evidence supporting either of these arguments?
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>>
Why can I get extreme pleasure and even orgasm from being fucked in the ass as a male? What is the evolutionary purpose of that?

Serious question.
>>
>>9454997
Look in the mirror fagglehorn.
>>
>>9453829
>>9453887
Being gay is not "normal" using that definition, no. So what, though.
>>
>>9455272
I can't.
>>
>>9454294
>>9455004
This

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Is Grover's Algorithim the hardest cross discipline subject to understand?

https://courses.cs.washington.edu/courses/cse599d/06wi/lecturenotes12.pdf
>>
No

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can someone be born without dopamine or the lack there of to process it?
>>
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Parkinsons, if you allow for time to let your dopamine production die down it passes your genetic criteria
>>
>>9454106
Neurotics.
>>
>>9454335
No...
>>
>>9454106
My brother has ADD, it's causing a lack of dopamin i think

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So, my grandparents brought this stuff up at dinner a couple of days ago. They've kept it around the house forever, and used it on me plenty of times as a kid. It's horse medicine, and it's great stuff. They purchased (a bunch of) it in Ecuador in the Sixties.

Does it or anything like it still exist? Can I get more, or perhaps order the ingredients and concoct my own?
7 replies omitted. Click here to view.
>>
>>9452655
yes
>>
>>9452655
Yes. It's making fun of redditors
>>
>>9452655
hor meme
>>
>>9452522
Look man if it doesn't have cocaine in it, it's not worth keeping around. I mean the bottle is cool and all, but that's about it.
>>
Sell it and use the money to buy drugs.

Help me understand how Bragg's Law works.

What I don't understand is how interference works. Every single explanation out there says that the two incoming X-Ray beams are reflected from the crystal planes and there are the two outgoing beams and *BOOM MAGIC* they interfere and they add up. But why? Literally every diagram like pic related only shows the two leaving beams parallel to each other and not interfering at all. Wtf is going on here?

Is it even real interference or is it just that many parallel beams have a more intense mark in the detector/on the film?

For interference to happen, shouldn't the two (or more) outgoing beams be not only parallel but actually in line?

What am I missing?
14 replies omitted. Click here to view.
>>
>>9454937
Does this help? Won't let me upload pictures
https://chem.libretexts.org/@api/deki/files/12295/Bragg'sLaw.jpg?revision=1&size=bestfit&width=444&height=236
>>
>>9455210
>You get a geometric pattern of light and dark spots
But the X ray detector is positioned where the brightest spot is then, right?

>>9455242
Yeah, I guess it is. It's still kinda weird that nowhere did I read that it's similar to the double slit experiment or diffraction grating.

So in essence, what we really get is pic related (sort of), but we are only interested in the angle that corresponds to the "central bright fringe"?
>>
>>9455254
They look at the entire pattern to determine the angles. Of course, that's when they used film. Maybe they scan the detector and measure one pixel at a time these days. But you need the whole thing.
Damn, I wish I could upload an image.
Think of the two-slit experiment. The spot directly between the 2 slits is bright. Because it's an equal distance from slit A and slit B. The waves travel the same distance, so they arrive in synch and reinforce. A little to one side they're out of phase and the screen is dark. A little further and the path difference is exactly one wavelength, so they reinforce again. Dark. Bright when the path lengths differ by two wavelengths, and so on.
From the wavelength of the light and the spacing of the dark lines on the screen you can calculate the distance between the slits. Follow?
Each successive peak corresponds to the next angle at which the difference in path-lengths between slit A and slit B is an integer multiple of the wavelength.
In Bragg diffraction you are calculating the equivalent of spacing between slits -- the spacing between atoms in the crystal. .
>>
>>9454937
How the fuck do you even study solid state without actually understanding optics first.
>>
>>9455266
>In Bragg diffraction you are calculating the equivalent of spacing between slits -- the spacing between atoms in the crystal.
Yeah, I get it now, thank you. It's weird to me that nowhere do you find this sort of comparison in any textbook or even online article. Or maybe it's obvious and I'm just dumb. But I'm not the only one since I've found forum threads on Quora and other websites asking the same thing: how does interference actually occur in the textbook diagrams for Bragg's Law.

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so if and this is a big if planet 9 is discovered to be real can we all agree that it will be named nibiru ? it just seems like such a fitting and perfect name for the hypothetical planet
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>>
>>9448817
We could use the Windows naming convention and call it planet 10.
>>
>>9448948
If you call out a jew for a real crime, are you still an antisemite?
>>
>>9448948
Who cares, we'd all be dead anyways.
>>
>>9448817
If it isn't named Yuggoth there will be blood.
>>
>>9454635
of course you are - truth is never a defense against the charge of racism. like the politician who had a bunch of blacks demanding he be forced out of of office for using the word 'niggardly'. when informed of their stupidity for not knowing what the word meant, they doubled down and insisted he still needed to go because it was his fault for making them think he used a bad word

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how do you draw a line that is perpendicular to 3 axes?
14 replies omitted. Click here to view.
>>
>>9452697
animations can be drawn.
>>
>>9452404
Easy, draw a line. It is perpendicular to all dimensions except for the one that it is in. As long as we can accept that there are at least 4 dimensions, any line that you draw will always be perpendicular to 3.
>>
>>9452396
by not drawing the other axes
>>
>>9452396
How do you draw a line that is perpendicular to 2 axes? A piece of paper only has 2 axes
>>
not possible to physically make something such that this is true, but it could be represented on paper or in a 3d model, albeit hard to read

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Why do people deny that IQ matters in daily life?
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>>
>>9446840
I REALLY don't like this graph.
Almost all of these countries are European, and they're heavily interlocked culturally.

There's even a schism between Western and Eastern Europe on this shit.
>>
>>9455033
>working memory
>IQ
What?
>>9454881
>also anyone have enough intelligence to take an IQ test and score well, those people are just not trying at all
Wrong, unless you're doing an online meme test
>>9454016
A lot of average or stupid people even have a disdain for intelligence. They want to be normal to fit in and belong to their community.
>>
>>9455142
You can only make intuitive connections if you can hold the variables in your brain.

The easiest path will reveal itself if you can see it because 1+1=2, but if you can't see it you'll always be trying 1+1=2.5
>>
>>9454880
>>9454881

You guys dont even know wgat intelligence is. Its an ill defined social construct. By the nature of the complexity of the brain and out own faulty intuitions we will never get a construct that satisfies what you seek to measure (because you cant even define it). Atleast iq has some predictove validity and the g factor isnt completely arbitrary. Tbh i imagine many cognitive tests share an arbitrariness.
>>
Because it makes them feel better.

>there are people on this board RIGHT NOW that are too stupid to understand how map projections work
Is that why so many idiots think its flat?
https://en.wikipedia.org/wiki/Map_projection
>>
It should be illegal to be this autistic.

Terrance Tao has proven Newman''s conjecture, putting himself on the track to prove the Reimann Hypothesis


https://arxiv.org/abs/1801.05914

Why haven't you bowed to our generation''s Gauss, if such a title would even begin to describe his genius?
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>>
>>9455098
What part of "serious field" do you not understand?
>>
>>9455119
Greatest country in the world: US of A. I'm told it's like this the world over and even worse in some places like France by colleagues, though.
>>
>>9450742
The virgin matematician
>Writes complex proofs that no one understands
The Chad computer scientist
>Doesn't even understand math, just lets the computer handle it
>>
>>9455082
I feel bad for laughing at this. Sorry, mate.
>>
>>9454797
>inter-dimensional fortress brain: polygamy

>>9454738
also, not sure if wife was asshole's wife or if she was person I admired the most's wife. She was always nice to me even though I could tell she didn't really like me.

>Frobenoid geometrie

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Was it a boondoggle?
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>>
>>9454397
Originally, no. However, because the government had their hands into it up to their elbows it became boondoggle. At least we got lots of cool tech we can use everyday because of it. Now NASA is completely fucking wrecked and subverted. It is filled with nothing but grant chasers now.
>>
>>9454397

No, it wasn't and don't let anyone tell you it was. The STS program did a lot for aerospace research and materials research, more than enough to make the program worthwhile. It's crowning achievement, the International Space Station, would have been considered utter lunacy if you had suggested such a thing to someone in 1960. Boeing's recent XS-1 vehicle is proof that the STS concept works.

Now, whether or not it was the most practical transportation device available is another question. SpaceX has shown that traditional rockets could have done what the STS did at a lower cost, a huge black eye for NASA and the entire establishment. Perhaps if NASA was more committed to it's original shuttle concept (a 5-10 person vehicle with no cargo bay) and the Pentagon more committed to it's X-20 project the STS wouldn't have existed as it did.
>>
>>9454712

$100 Billion has already been earmarked for the B-21 program, and about $200 Billion for Columbia Class submarines. $400 billion is not much for a fighter jet considering it will be THE fighter jet the Air Force, Navy and Marines will use. Which is to say it's a procurement for three branches instead of one, which would be about $130 Billion each. That's very average considering how important fighter jets are.
>>
>>9455214
ISS is essentially Mir 2.0, and, lik Mir, could have been built and operated without STS.
>>
The main problem is that we expect space exploration to be free of casualties and tragedies. It won't be. Many already died, many more will. This is the nature of exploration.

You're, quite literally, strapping people to a missile and shooting them into the sky. It's gonna get ugly occasionally. We need to carry on, not treat every space accident like a fucking unmitigated disaster.



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